Board perforator and cutter



Sept. 30, 1969 a. o. WELCH ETAL 3,469,477

BOARD PERFORATOR AND CUTTER Filed May 10, 1967 2 Sheets-Sheet 1 Fig.l

INVENTORS George D. Welch Leonard L. Donuhe AT TORN EY Sept. 30, 1969 a.D. WELCH ET AL 3,469,477

BOARD PERFORATOR AND CUTTER 2 Sheets-Sheet 2 Filed May 10, 1967 Fig. 2

INVENTORS George D. Welch BY Leonard L. Donohe ATTORNEY United StatesPatent Office Patented Sept. 30, 1969 US. Cl. 838 1 Claim ABSTRACT OFTHE DISCLOSURE Relative to a board perforator and cutter, as disclosedin US. Patent 2,345,072, there is disclosed herein an improvementwherein the lowering and raising of the axis of the upper rotary knifeblade, for respectively cutting a board or perforating a board passingbetween it and a lower knife blade, is accomplished by the sequence ofadvancing or retracting an air cylinder piston and an attached spur geareach, which rotates, approximately 180 one way or the other, a spurgear, rotating a cam, and causing lowering or raising of the twoslidable, spring loaded slide plates in which the upper knife rotor isjournalled.

Background of the invention Prior cutting and perforating machines,primarily for use on plaster board or the like, such as that disclosedin US. Patent 2,345,072, also included a cam, the rotation of whichlowered and raised two slidable spring loaded slide plates in which theupper knife rotor was journalled. Rotation of the prior cam, however,con sisted of one uniform speed continuous single revolution of the cam,driven by engagement of a positive drive jaw clutch which was driven bythe same drive means that drove the two rotary knives. Although notshown in the prior patent, a drag brake was also required to stop therotation of the cam immediately on disengagement of the associated jawclutch, which, if the jaw clutch started to open somewhat early,resulted in uneven perforations, cutoffs and board lengths. With theprior complete revolution of a cam providing the upper and lowerpositions of the upper knife rotor, adjustment of these positionsrequired replacement of the cam.

Summary of the invention The present invention relates to thecombination, with a machine for alternatively cutting or perforatingboard, of improved means for lowering and raising the upper knife rotor,to thus change to cutting and to perforating positions, respectively.Briefly, the improved means comprise an independent drive means forrapidly rotating the cam which causes the vertical movement of the upperknife rotor, preferably rotating the cam less than 180 and reversing anequal amount, to provide easily controlled amounts of lowering andraising.

Drawings FIG. 1 is an end view of a board perforator and cutter,embodying the present invention.

FIG. 2 is a right-side view of the drive portion of the machine of FIG.1, which is the portion adjacent the end shown in FIG. 1. a

Preferred embodiment Referring to the drawings, it will be seen thatthere is illustrated a machine very similar in many respects to themachine disclosed in Patent 2,345,072, issued Mar. 28, 1944. In thepresent disclosure, the means for driving the rotor shifting cam isdifferent, and are identified in the drawings by numerals starting withthe numeral 200. Lower numerals will be seen to correspond with theidentifying numerals used in US. Patent 2,345,072, relative to elementsof the present invention which are similar to the elements of the saidpatent.

In the drawings there will be seen the machine bed 10 mounted on feet 11and supporting two end frames, only the left end frame 13 being shown inFIG. 2, in which end frames the two ends of lower rotor 16 are solidlyjournalled, only left end 15 being shown. The rotor 16 carries fourknives 17, 18, 19 and 20, spaced apart on its periphery.

A suitable solid continuous drive is provided for lower rotor 16 at theremote end thereof not shown in the drawings.

A continuation 31 of the end 15 of the rotor 16 is journalled in asupplemental end frame 32 mounted on the bed 10, and carries a gear 33continuously meshing with a gear 34 of equal pitch diameter mounted on astub shaft 35 journalled in the frame member 32. To one face of the gear34 is secured one member 36 of an Oldham coupling of well understoodconstruction, while the mating element 37 of said coupling has securedtoaits outer face a jaw clutch element 38. The elements 37 and 38 areaxially loosely mounted on a shaft 40 extending from one end of an upperrotor 41. The shaft 40 is journalled in suitable bearings in a bearingcarriage, or slide plate 43, vertically slida-bly mounted respectivelyin the end frame 13, as is also a shaft at the other end of upper rotor41. The slide plate 43 is guided for vertical movement in a guideway 44formed in the end frame 13. The guide plate is constantly supported andurged upwardly by a spring 45. With the other end of the rotor 41similarly mounted, it will be seen to be transaxially shiftable towardand away from rotor 16.

Integral with plate 43 is a platform 46 formed to hingedly mount apintle 48 to which are fixed a pair of yoke arms 49 provided with shoes50 diametrically oppositely received in an annular groove 51 formed in aclutch element 52 fixed on shaft 40 adapted to mate with clutch element38. At least one of said arms is provided with an extension 53 withwhich is associated a coiled spring 54 urging said yoke arms to swing ina counter-clockwise direction; as viewed in FIG. 2, to move said clutchelement 52 into cooperative relation with the element 38; but saidelement 52 is normally restrained against such movement and held in theposition illustrated in FIG. 2 by the engagement of a trip dog 55 withthe thickened portion 56 of an annular cam collar 57 integral with orfixed to said element 52.

As is clearly shown in FIG. 2, the dog 55 is reciprocably mounted in alug 58 carried on said platform 46, and is held in position by a finger59 on a rockshaft 60 journalled in bearings 61, 61 depending from theplatform 46, and carrying a lever 62 with which is associated a coiledspring 63 tending to rotate said lever in a clockwise direction asviewed in FIG. 2 and thereby holding the dog 55 in its illustratedposition.

It will be obvious that the driving train thus far described willproduce continuous rotation of the rotor 16, and will effect rotation ofthe rotor 41 only when the clutch element 52 is engaged with the clutchelement 38; and that the provision of the Oldham coupling permits thetransmission of movement from the stub shaft 35 to the rotor 41 whetheror not those members are in axial alignment. A single knife '64 iscarried by the rotor 41.

In the illustrated positions of the parts, the dog 55 cooperates withthe thickened portion 56 of the cam collar 57 to hold the clutch element52 out of engagement with the element 38. counterclockwise movement ofthe lever 62, however, in opposition to the spring 63, Wlll withdraw thedog 55 to permit the spring 54 to move the element 52 into cooperativerelation with the constantly rotating element 38 to drive the element 52and the rotor 41. If the lever 62 is now promptly released, the spring63 will urge the dog 55 into engagement with the peripheral surface ofthe collar 57 of the rotating element 52; and as said element rotates,the thin portion of the collar will come into registry with the dog 55to permit said dog to move upwardly into contact with the left-hand,cammed face of said collar. Thus, as the rotor 41 approaches completionof a revolution, the dog 55, acting on the cammed face 56 of the collar57, will shift the element 52 to the right to disengage said elementfrom the element 38. Preferably, a spring-pressed brake not shown isassociated with a projecting portion of the end not shown of the rotor41 to stop said rotor promptly upon disengagement of said clutchelements, the brake 65 being mounted to partake of the transaxialmovement of the rotor 41.

Beyond the supplemental end frame 32, the extension 31 carries abevelled gear 66 meshing with a gear 67 fixed on a shaft 68 journalledin suitable brackets 69 and 70. The shaft 68 carries a sprocket 71connected, by a chain 72 to drive a double sprocket 73, 74 suitablyjournalled on the machine frame. The chain 72 engages the portion 73 ofthe last-named sprocket; and a control chain 75 hangs loosely on thesprocket portion 74, said chain 75 carrying one or more suitablypositioned trip elements 76. It will be clear from the above that thechain 75 is driven with the continuously rotating rotor 16, and, atpredetermined points in the cycle of the rotor 16, a trip element 76will be caused to engage the lever 62 to swing the same in acounterclockwise direction to withdraw the dog 55 to permit engagementof the clutch element 52 with the element 38, and that thereupon therotor 41 will be turned through one revolution, upon the completion ofwhich the now-released dog 55 will cause disengagement of the element 52from the element 38, and the said spring pressed brake will stop therotor 41.

Of course, the chain 75 will be so associated with the sprocket 74 as totrip the clutch mechanism at a time such as to bring the knife 64 intovertically downwardly directed position at a time to cooperate with oneof the knives on the rotor 16. It will be obvious that the chain 75 canbe so designed and proportioned as to cause the knife 64 to cooperatewith any one of the knives on the rotor 16 upon each revolution of therotor 16, or to cooperate with successive knives on the rotor 16. Thus,depending upon the selection of a chain 75 of suitable length or withsuitably spaced trip elements 76, the rotor 41 can be caused to make onerevolution for each revolution of the rotor 16, or one revolution foreach one and one-fourth revolutions of the rotor 16, or one revolutionfor each one and one-half revolution of the rotor 16, or one revolutionfor each one and three-fourths revolutions of the rotor 16, or onerevolution for any other number of revolutions of the rotor 16 in thesame arithmetical progression. Thereby, the machine can be caused to cutmaterial traveling therethrough to any desired length greater than theperiphery of the orbit of the knives on the rotor 16 by any desiredmultiple of onefourth that length.

It is often desirable, particularly in working upon plaster board, tocause a cut-off machine to perforate the board at stated intervalsbetween severing operations. It is for that reason that the rotor 41 ismounted for transaxial movement relative to the rotor 16, and we haveprovided means for automatically shifting the rotor 41 between thatposition in which the knife 64 will cooperate with one of the knives onthe rotor 16 to sever the board and that position in which the knife 64will cooperate with one of the knives on the rotor 16 merely toperforate the board without severing it. Referring, again, to FIGS. 1and 2, it Will be seen that the slide plate 43 mounts a roller 77adjacent its upper end, and that a cam 78 engages said roller to holdthe slide plate 43 down against the tendency of the spring 45. It willbe obvious of course that the other end of the rotor 41 is journalled ina similar slide plate provided with a similar roller with whichcooperates a similar cam which is carried on the same cam shaft 79 withthe cam 78.

Alternative means may be provided by which rotation of shaft 79 willeffect vertical movement of slide plate 43 and rotor 41, such as, forexample although not shown, forming shaft 79 to include an eccentricportion, in place of the cam 78, which eccentric portion is journalledin an extended portion of slide plate 43.

On an extension 200 of cam shaft 79 there is mounted a spur gear 202.Dispersed above and engaged with spur gear 202 is a horizontallydisposed spur gear rack 204. At each side of spur gear 202, shaftextension 200 is journalled in bearing supports 206, 206, and atop eachbearing support 206 is a small pillow block 208. A rack hold down wheel210, with 'a small shaft 212 is rotatably mounted in the pillow blocks208, 208, with the wheel 210 atop the spur gear rack 204 to hold therack firmly engaged with spur gear 202 as the rack is caused to movelongitudinally to rotate spur gear 202.

An air cylinder 214 is fixedly mounted on a side platform 216 extendingoutwardly from frame 32. Air cylinder 214 includes an axiallyreciprocatory piston rod 218 aligned with and aflixed to spur gear rack204. Two high pressure air supply hoses 220 and 222 are connected one toeach end of air cylinder 214 for causing reciprocatory movement ofpiston rod 218 and spur gear rack 204. Pressure in hose 220 moves thespur gear rack 204, to an extended position relative to the aircylinder, and subsequent pressure in hose 222 returns the spur gear rackto a normal retracted position. An adjustable stop 224 permitsadjustment of the extent of the retraction of the spur gear rack 204.

High pressure air is supplied to either hose 220 or hose 222 inaccordance with the position of an electrically operated four way aircontrol valve 226. A controlled source of high pressure air is suppliedto valve 226 through supply pipe 228 having therein an air regulator230.

Actuation of valve 226 is accomplished in a timed frequency to providefor the cutting of board 232 at preselected lengths, it being understoodfrom decriptive matter further above that intermediate of said cuttingof said board the knife 64 may be made to cooperate with one of theknives on rotor 16 merely to perforate the board without severing it.Adjacent to the sprocket 71, and on the same shaft 68, is sprocket 234,rotating simultaneously with sprocket 71. Mounted above sprocket 234 isa sprocket 236, to which is fixedly mounted a series of sprockets 238,238, 238 sprocket 236 is driven from sprocket 234 by chain 240, thusdriving sprockets 238, 238', 238". Each sprocket 238 has suspendedtherefrom a chain 242, 242, 242", each of different pre-selected lengthand each carrying one or more suitably positioned trip elements 244. Anelectrical limit switch 246 is mounted above sprockets 238, and includesa lever 248 which is adjustable for actuation selectively by the tripelement 244 of any one of the chains 242, 242 or 242". A coiled spring250 maintains lever 248 in a normal vertical position until moved bytrip element 244. Limit switch 246 is connected to valve 226 by wires252, 252.

When lever 248 is moved counter-clockwise, FIG, 2, by trip element 244,switch 246 activates valve 226, allowing high pressure air to flow intoair cylinder 214 through hose 220, and allowing air in hose 222 toescape to atmosphere. Piston rod 218 and spur gear rack 204 move left,FIG. 1, to an extended position, rotating spur gear 202 and cam 78counter-clockwise, slightly less than half a revolution. Cam 78, by itsshape, thus moves roller 77 and its associated slide plate 43 downward,also moving rotor 41 and knife 64 downward. It will be understood thatthis downward movement will be timed to occur as knife 64 is beingrotated to cooperate with one of the knives on rotor 16. In the downwardposition the knife 64 cause the board to be severed, rather than merelyperforated, as occurs when rotated in its upward position.

Upon release of lever 248, it is returned to a normal vertical positionby spring 250. Switch 246 activates valve 226 to return spur gear rack204 to its normal retracted position, rotating the spur gear 202 and cam78, clockwise, to normal positions. Adjustment of this normal position,to adjust for various thicknesses of boards to be perforated, can beaccomplished readily by adjustment of adjustable stop 224, on aircylinder 21 4.

It will be obvious that the minimum length of board which can beperforated or cut with the present machine is determined by theperiphery of the orbit of the cutting edge of the knife 64. In practicethis length is usually 48 inches. Since the rotor 16 is provided withfour knives, equally spaced, it will be obvious that the machine iscapable of cutting lengths greater than 48 inches by any desiredmultiple of 12 inches.

Having completed a detailed disclosure of the preferred embodiment ofour invention, so that others may practice the same, we contemplate thatvariations may be made without departing from the essence of theinvention.

We claim:

1. A cut-off machine comprising a pair of knife-carrying rotors mountedto cooperatively selectively perforate or sever a horizontally movinglength of board material therebetween, means for driving said rotors,and means for transaxially moving one of said rotors relative to theother fixed axis rotor for respectively perforating or severing saidboard material, said means for moving said one rotor transaxiallycomprising vertically slidably mounted end plates in which said onerotor is journalled and a separately driven cam mounted relative to saidend plates whereby rotation of said cam transaxially moves said endplates and said one rotor journalled therein, means for rotating saidcam less than one complete revolution, in one direction for raising andthe opposite direction for lowering said end plates and said rotorjournalled therein, said means for rotating said cam comprising a shafton which said cam is mounted and a spur gear mounted on said shaft forrotating said shaft and said cam, a spur gear rack engaging said spurgear, a high pressure air powered cylinder having a piston thereinaflixed to said spur gear rack for selectively timed reciprocatorymovement of said spur gear rack, and electrically actuated four-way aircontrol valve having means for supplying high pressure air to either ofthe two respective ends of said high pressure air powered cylinder formoving said piston and spur gear rack in one or the other of thedirections of their extent, and selective control means for electricallyactuating said four-way valve comprising a plurality of coaxial spindlesrotatably driven by said means for driving said rotors having chainsthereon with selectively positioned trip elements on each said chain, alever adjustably mounted for actuation thereof selectively by any one ofsaid chain and trip element combinations, and an electric switchoperated by said lever, said electric switch being connected to saidelectrically activated valve with means to provide activation of saidvalve upon mechanical activation of said switch.

References Cited UNITED STATES PATENTS 46,448 2/1-865 Clarke 83-8 X2,169,575 8/1939 Youngfelt et al. 83-344 X 2,272,702 2/ 1942 Haegele83-8 2,345,072 3/1944 Rosenleaf et al. 83344 X 3,202,029 8/1965 Morath83528 X 3,296,909 1/ 1967 Hudak et al 83-305 FRANK T. YOST, PrimaryExaminer U.S. Cl. X.R.

